diff options
Diffstat (limited to 'src/compiler/nir/nir_lower_alu_to_scalar.c')
| -rw-r--r-- | src/compiler/nir/nir_lower_alu_to_scalar.c | 210 |
1 files changed, 210 insertions, 0 deletions
diff --git a/src/compiler/nir/nir_lower_alu_to_scalar.c b/src/compiler/nir/nir_lower_alu_to_scalar.c new file mode 100644 index 00000000000..0a27e66cf0f --- /dev/null +++ b/src/compiler/nir/nir_lower_alu_to_scalar.c @@ -0,0 +1,210 @@ +/* + * Copyright © 2014-2015 Broadcom + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice (including the next + * paragraph) shall be included in all copies or substantial portions of the + * Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS + * IN THE SOFTWARE. + */ + +#include "nir.h" +#include "nir_builder.h" + +/** @file nir_lower_alu_to_scalar.c + * + * Replaces nir_alu_instr operations with more than one channel used in the + * arguments with individual per-channel operations. + */ + +static void +nir_alu_ssa_dest_init(nir_alu_instr *instr, unsigned num_components) +{ + nir_ssa_dest_init(&instr->instr, &instr->dest.dest, num_components, NULL); + instr->dest.write_mask = (1 << num_components) - 1; +} + +static void +lower_reduction(nir_alu_instr *instr, nir_op chan_op, nir_op merge_op, + nir_builder *builder) +{ + unsigned num_components = nir_op_infos[instr->op].input_sizes[0]; + + nir_ssa_def *last = NULL; + for (unsigned i = 0; i < num_components; i++) { + nir_alu_instr *chan = nir_alu_instr_create(builder->shader, chan_op); + nir_alu_ssa_dest_init(chan, 1); + nir_alu_src_copy(&chan->src[0], &instr->src[0], chan); + chan->src[0].swizzle[0] = chan->src[0].swizzle[i]; + if (nir_op_infos[chan_op].num_inputs > 1) { + assert(nir_op_infos[chan_op].num_inputs == 2); + nir_alu_src_copy(&chan->src[1], &instr->src[1], chan); + chan->src[1].swizzle[0] = chan->src[1].swizzle[i]; + } + + nir_builder_instr_insert(builder, &chan->instr); + + if (i == 0) { + last = &chan->dest.dest.ssa; + } else { + last = nir_build_alu(builder, merge_op, + last, &chan->dest.dest.ssa, NULL, NULL); + } + } + + assert(instr->dest.write_mask == 1); + nir_ssa_def_rewrite_uses(&instr->dest.dest.ssa, nir_src_for_ssa(last)); + nir_instr_remove(&instr->instr); +} + +static void +lower_alu_instr_scalar(nir_alu_instr *instr, nir_builder *b) +{ + unsigned num_src = nir_op_infos[instr->op].num_inputs; + unsigned i, chan; + + assert(instr->dest.dest.is_ssa); + assert(instr->dest.write_mask != 0); + + b->cursor = nir_before_instr(&instr->instr); + +#define LOWER_REDUCTION(name, chan, merge) \ + case name##2: \ + case name##3: \ + case name##4: \ + lower_reduction(instr, chan, merge, b); \ + return; + + switch (instr->op) { + case nir_op_vec4: + case nir_op_vec3: + case nir_op_vec2: + /* We don't need to scalarize these ops, they're the ones generated to + * group up outputs into a value that can be SSAed. + */ + return; + + case nir_op_unpack_unorm_4x8: + case nir_op_unpack_snorm_4x8: + case nir_op_unpack_unorm_2x16: + case nir_op_unpack_snorm_2x16: + /* There is no scalar version of these ops, unless we were to break it + * down to bitshifts and math (which is definitely not intended). + */ + return; + + case nir_op_unpack_half_2x16: + /* We could split this into unpack_half_2x16_split_[xy], but should + * we? + */ + return; + + case nir_op_fdph: { + nir_ssa_def *sum[4]; + for (unsigned i = 0; i < 3; i++) { + sum[i] = nir_fmul(b, nir_channel(b, instr->src[0].src.ssa, + instr->src[0].swizzle[i]), + nir_channel(b, instr->src[1].src.ssa, + instr->src[1].swizzle[i])); + } + sum[3] = nir_channel(b, instr->src[1].src.ssa, instr->src[1].swizzle[3]); + + nir_ssa_def *val = nir_fadd(b, nir_fadd(b, sum[0], sum[1]), + nir_fadd(b, sum[2], sum[3])); + + nir_ssa_def_rewrite_uses(&instr->dest.dest.ssa, nir_src_for_ssa(val)); + nir_instr_remove(&instr->instr); + return; + } + + LOWER_REDUCTION(nir_op_fdot, nir_op_fmul, nir_op_fadd); + LOWER_REDUCTION(nir_op_ball_fequal, nir_op_feq, nir_op_iand); + LOWER_REDUCTION(nir_op_ball_iequal, nir_op_ieq, nir_op_iand); + LOWER_REDUCTION(nir_op_bany_fnequal, nir_op_fne, nir_op_ior); + LOWER_REDUCTION(nir_op_bany_inequal, nir_op_ine, nir_op_ior); + LOWER_REDUCTION(nir_op_fall_equal, nir_op_seq, nir_op_fand); + LOWER_REDUCTION(nir_op_fany_nequal, nir_op_sne, nir_op_for); + + default: + break; + } + + if (instr->dest.dest.ssa.num_components == 1) + return; + + unsigned num_components = instr->dest.dest.ssa.num_components; + nir_ssa_def *comps[] = { NULL, NULL, NULL, NULL }; + + for (chan = 0; chan < 4; chan++) { + if (!(instr->dest.write_mask & (1 << chan))) + continue; + + nir_alu_instr *lower = nir_alu_instr_create(b->shader, instr->op); + for (i = 0; i < num_src; i++) { + /* We only handle same-size-as-dest (input_sizes[] == 0) or scalar + * args (input_sizes[] == 1). + */ + assert(nir_op_infos[instr->op].input_sizes[i] < 2); + unsigned src_chan = (nir_op_infos[instr->op].input_sizes[i] == 1 ? + 0 : chan); + + nir_alu_src_copy(&lower->src[i], &instr->src[i], lower); + for (int j = 0; j < 4; j++) + lower->src[i].swizzle[j] = instr->src[i].swizzle[src_chan]; + } + + nir_alu_ssa_dest_init(lower, 1); + lower->dest.saturate = instr->dest.saturate; + comps[chan] = &lower->dest.dest.ssa; + + nir_builder_instr_insert(b, &lower->instr); + } + + nir_ssa_def *vec = nir_vec(b, comps, num_components); + + nir_ssa_def_rewrite_uses(&instr->dest.dest.ssa, nir_src_for_ssa(vec)); + + nir_instr_remove(&instr->instr); +} + +static bool +lower_alu_to_scalar_block(nir_block *block, void *builder) +{ + nir_foreach_instr_safe(block, instr) { + if (instr->type == nir_instr_type_alu) + lower_alu_instr_scalar(nir_instr_as_alu(instr), builder); + } + + return true; +} + +static void +nir_lower_alu_to_scalar_impl(nir_function_impl *impl) +{ + nir_builder builder; + nir_builder_init(&builder, impl); + + nir_foreach_block(impl, lower_alu_to_scalar_block, &builder); +} + +void +nir_lower_alu_to_scalar(nir_shader *shader) +{ + nir_foreach_function(shader, function) { + if (function->impl) + nir_lower_alu_to_scalar_impl(function->impl); + } +} |